1. Field of the invention
The present invention relates to improved topical compositions containing inorganic metal compounds.
2. Background Art
Cosmetic compositions for inhibiting perspiration in hot and humid weather or preventing an axillary odor due to perspiration have conventionally contained, as an antiperspirant, an inorganic metal compound having an astringent action on the skin. For example, aluminum chloride, aluminum hydroxychloride, zirconium hydroxychloride, zinc chloride, zinc sulfate or the like have been incorporated. Such cosmetic compositions have been supplied in forms such as a lotion, emulsion, spray, gel, gel stick and the like.
Among them, a gel stick type composition containing a gelling agent consisting of an n-acyl amino acid amide and 12-hydroxystearic acid, an oily substance and an antiperspirant as described above has been proposed (International Patent Publication No. Hei 7-506833; WO93/23008). Incorporation of a conventionally employed antiperspirant in a gel composition, however, involves problems wherein a whitening (i.e. white residue) appears on the dried skin, for example, the underarm skin to which the composition has been topically applied to, impairing the appearance and feeling upon use.
On the other hand, a dialkylphosphate polyaluminum salt available by reacting a dialkylphosphate (or salt thereof) with a basic polyaluminum salt has been proposed as an oil gelling agent (Japanese Patent Laid-Open No. Hei 1-193278; U.S. Pat. No. 5,124,361). Application examples of it to topical compositions such as antiperspirant cosmetic compositions are however not disclosed.
An antiperspirant spray composition comprising an antiperspirant, a phosphoric acid type anionic surfactant such as polyoxyethylene alkyl ether phosphoric acid, an oil, silicic acid anhydride, ethyl alcohol and a propellant has also been proposed (Japanese Patent Laid-Open No. Hei 9-157147). The compositions disclosed therein however relates to a powder spray.
The present invention relates to a composition containing a specific phosphate or salt thereof (including its mixtures), together with a zirconium salt and/or an aluminum zirconium complex salt.
According to the present invention, there is thus provided a topical composition, which comprises a phosphate(s) represented by the following formula(s) (1) and/or (2): 
(wherein, R1 and R2 each represents a linear or branched hydrocarbon group having 8 to 36 carbon atoms) or a salt thereof, and a zirconium salt and/or aluminum zirconium complex salt.
All publications cited herein are incorporated by reference.
The phosphate to be used as Component (A) in the present invention is a phosphate ester, its salts, and mixtures thereof represented by formula (1) and formula (2). A phosphate monoester is represented by formula (1) and a phosphate diester is represented by formula (2). The hydrocarbon group represented by R1 or R2 in the formulas may be any hydrocarbon group which is saturated or unsaturated, and linear or branched insofar as it has 8 to 36 carbon atoms. Particularly preferred from the viewpoint of gelling capacity to form a gel composition are saturated hydrocarbon groups, more preferably saturated and branched hydrocarbon groups. R1 and R2 may be the same or different.
Specific examples of such hydrocarbon groups include octyl, nonyl, decyl, dodecyl, undecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, heneicosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, decenyl, dodecenyl, undecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl, eicosenyl, heneicosenyl, docosenyl, tricosenyl, tetracosenyl, pentacosenyl, hexacosenyl, octadienyl, nonadienyl, decadienyl, dodecadienyl, undecadienyl, tridecadienyl, tetradecadienyl, pentadecadienyl, hexadecadienyl, heptadecadienyl, octadecadienyl, nonadecadienyl, eicosadienyl, heneicosadienyl, docosadienyl, tricosadienyl, tetracosadienyl, pentacosadienyl, hexacosadienyl, 2-hexyldecyl, 2-octylundecyl, 2-decyltetradecyl, eicosadecyl, 2-ethylhexyl, 1,1,3,3-tetramethylbutyl, 3,7-dimethyloctyl, 3,7-dimethyloctan-3-yl, 2-hexyldecyl, 2-heptylundecyl, 2-octyldodecyl, 3,7,11-trimethyldodecyl, 3,7,11,15-tetramethylhexadecyl, 3,5,5-trimethylhexyl, 2,3,4-trimethylpentan-3-yl, 2,3,4,6,6-pentamethylheptan-3-yl, isostearyl, 2-decyltetradecyl, 2-dodecylhexadecyl, 2-tetradecyloctadecyl and 2-hexadecyleicosadecyl groups.
Among them, saturated branched hydrocarbon groups having 12 to 24 carbon atoms are particularly preferred.
These phosphates may be used in the acid form, but are usable as salts such as salts of an alkali metal such as sodium, potassium, or the like, salts of an alkanolamine such as monoethanolamine, diethanolamine, triethanolamine, or the like, or salts of a basic amino acid such as lysine, arginine, or the like. Phosphates in the acid form are economically preferred because they can be prepared at a lower cost.
As Component (A), the phosphate containing a phosphate monoester (1) and a phosphate diester (2) in combination is preferred. The phosphate containing the monoester and diester in a (1):(2) ratio (weight ratio) ranging from 90:10 to 0.1:99.9, especially from 60:40 to 1:99 is preferred, because it exhibits good gel forming capacity.
The phosphate as Component (A) is available by reacting the corresponding aliphatic alcohol with a phosphorylating reagent such as diphosphorus pentaoxide, phosphorus oxychloride, or the like under conditions permitting formation of the monoester (1) and diester (2) in a desired ratio; and then neutralizing the reaction product as needed. The reaction product contains a small amount of triester, unreacted alcohol and the like, though depending on the nature of the raw materials and reaction conditions. Such triester and the like have less influence on the properties intended in the present invention.
As Component (A), one or more phosphates or salts thereof are usable. The addition of them in an amount of 3 to 10 wt. %, especially 4 to 8 wt. % based on the total composition is preferred in order to impart the resulting composition with excellent feeling upon use.
The zirconium salt or aluminum zirconium complex salt as Component (B) is a salt conventionally employed as an antiperspirant. Examples of the zirconium salt include zirconium chloride, zirconium hydroxychloride and zirconium compounds represented by the following formula (3):
ZrO(OH)2-myXyxe2x80x83xe2x80x83(3)
(wherein, X represents a halogen atom, nitrate ion, sulfate ion or sulfamate ion, y represents a number from 0.9 to 2, m represents a valence of X and 2-my represents a number of not less than 0).
Examples of the aluminum zirconium complex salt include aluminum zirconium chloride, aluminum zirconium chlorohydroxide, aluminum zirconium glycine complex, and aluminum zirconium propylene glycol complex.
As Component (B), commercially available products are also usable. Aluminum zirconium propylene glycol complexes include xe2x80x9cREZAL(copyright) 36 GPG Powderxe2x80x9d, xe2x80x9cREACH(copyright) AZP-908 PG Powderxe2x80x9d (each, product of Reheis, Inc.), and xe2x80x9cWestchlor(copyright) ZR41 PG ASP Powder (product of Westwood Chemical), while aluminum zirconium glycine complexes include xe2x80x9cREACH(copyright) AZP-908xe2x80x9d, xe2x80x9cREACH(copyright) AZP-908SUFxe2x80x9d, and xe2x80x9cREACH(copyright) AZP-902xe2x80x9d (each, product of Reheis, Inc.).
As Component (B), at least one of the compounds as described above is usable. Addition of the compound in an amount of 10 to 30 wt. %, especially 15 to 25 wt. % based on the total amount of the composition is preferred, because it brings about a high perspiration inhibiting effect and excellent feeling upon use. Addition of the compound in an amount exceeding the above range tends to deteriorate the feeling upon use.
The topical composition according to the present invention can be prepared by mixing, in an appropriate medium, Components (A) and (B) with the other components which will be described below. As the medium, an aqueous medium described below or a mixture thereof with a non-aqueous medium is usable. It is presumed that the zirconium salt or aluminum zirconium complex salt of a phosphate is formed in the composition thus prepared. Although it is possible to prepare the zirconium salt or aluminum zirconium complex salt of the phosphate in advance, and then incorporate it in the aimed topical composition, a process of directly adding Components (A) and (B) to a composition, thereby preparing the topical composition is more advantageous than the former process in view of convenience.
The aluminum zirconium complex salt of the phosphate is a novel compound.
Such a compound is available by reacting Components (A) and (B) in an appropriate medium. In one such case, the phosphate (1) and/or (2), or salt thereof is mixed and reacted with 0.01 to 1.1 equivalents of a zirconium salt and/or aluminum zirconium complex salt in an aqueous medium or a mixture of an aqueous medium with a non-aqueous medium. The reaction is effected at 10 to 90xc2x0 C., preferably 20 to 80xc2x0 C., for 0.5 to 8 hours. When a precipitate appears after completion of the reaction, it is filtered off. The solvent is also distilled off under reduced pressure to obtain the intended compound. The compound may be washed if necessary.
Examples of the aqueous medium usable here include water, methanol, ethanol, acetone, and isopropyl alcohol. They may be used either singly or in combination.
Examples of the non-aqueous medium include hexane, octane, decane, dodecane, isoparaffin, toluene, terpenes, cyclic or linear silicone oils.
As a mixed medium, a mixture of one aqueous medium and one non-aqueous medium or a mixture of a plurality of aqueous media and a plurality of non-aqueous media may be used.
The topical composition according to the present invention may further contain component (C), a liquid oil. The liquid oil is in liquid form at 25xc2x0 C. and may be either volatile or nonvolatile. Examples include hydrocarbons such as decane, dodecane, liquid paraffin, liquid isoparaffin, light liquid isoparaffin, mineral oil, squalane and squalene; eucalyptus oil, peppermint oil, camellia oil, Macadamia nut oil, avocado oil, yolk oil, olive oil, lanolin and jojoba oil; ester oils such as glycerol monooleate, isopropyl palmitate, isopropyl stearate, butyl stearate, isopropyl myristate, neopentyl glycol dicaprylate, diethyl phthalate, myristyl lactate, diisopropyl adipate, 2-ethylhexyl palmitate, 2-octyldodecyl myristate, neopentyl glycol di-2-ethylhexanoate, 2-octyldodecyl oleate and glycerol triisostearate; higher fatty acids such as isostearic acid and oleic acid; and silicone oils.
In the present invention, silicone oils ordinarily added to topical compositions are usable. Examples include dimethylpolysiloxane, high-polymerization-degree dimethylpolysiloxane, and methylphenylpolysiloxane; and cyclic dimethylpolysiloxanes such as octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane.
As the liquid oil, one or more of the above-described ones are usable. They are preferably added in an amount of 20 to 80 wt. %, especially 30 to 70 wt. % based on the total amount of the composition.
In the present invention, addition of such a liquid oil facilitates preparation of a thixotropic soft gel and thus its use is suited for obtaining a gel cosmetic composition.
The topical composition according to the present invention may further contain a solid fat, water, various surfactants, a humectant, an antiseptic, an antioxidant, a pharmaceutically effective ingredient, a perfume, a powder and the like.
The topical composition according to the present invention can be prepared, for example, by mixing an oil phase containing Component (A) and an aqueous solution of Component (B) while stirring and heating at 40xc2x0 C. to 80xc2x0 C.
The topical composition according to the present invention is usable as any one of a pharmaceutical and/or a cosmetic and it is particularly useful as an antiperspirant product or antiperspirant cosmetic composition.
The following examples further describe and demonstrate embodiments of the present invention. The examples are given solely for the purpose of illustration and are not to be construed as limitations of the present invention.